This invention relates primarily to an arrangement for selectively repelling insects from or attracting insects to a control station.
A discussion of historical approaches to addressing insect problems is detailed in U.S. Pat. No. 5,241,778, assigned to the present assignee and hereby incorporated by reference as if set forth in its entirety herein. The ""778 patent describes a method for attracting and eradicating insects in which a heartbeat sound attracts insects to a control station. According to the ""778 patent, by projecting a heartbeat sound from a speaker, one or more discrete zones can be established which attract mosquitoes and other insects. There remains a need, however, to increase the zone of influence of the established attractant zone as well as its efficacy.
U.S. Pat. No. 4,168,591 discloses a method that utilizes a combination of heat and moisture to attract insects.
U.S. Pat. No. 4,506,473 discloses a method for attracting blood-sucking insects using carbon dioxide.
Applicants"" co-pending parent application addresses the problem of wide-area, outdoor control of insect populations. However, there is an increasing need to control the population of blood sucking insects in an environmentally sensitive manner. The spread of the West Niles virus from tropical areas into dense population regions such as the Northeast section of the United States of America is but one example of the need to control insect populations.
What is needed in the art and heretofore has not been available is an improved apparatus for local control of insects. What is further needed is such an apparatus that is suitable for use both indoors and outdoors. The present invention satisfies these and other needs.
In one aspect, the invention provides a centralized system and method for controlling insect populations such as biting arthropods. In a preferred embodiment, a self-contained insect control station is used either alone or in coordination with other self-contained insect control stations. The invention utilizes sound waves as either an attractant or repellant in order to control pest populations in a target region. The sound waves to be employed can be selectively established to achieve the desired function. Thus, a simulated heartbeat sound or other suitable periodic low frequency sound enhanced by a resonator/soundboard (e.g., in the range of cps 20-500 cps, depending on the sound intensity and periodicity) can be employed as an attractant or as a repellant of insects such as mosquitoes and biting flies. The invention can achieve population control of insects through the use of one or more control stations that may be connected, directly or indirectly through other control stations, to a central distribution point.
The invention can make use of other factors, which may or may not be critical, depending on which insects are to be controlled and whether insect attraction or repulsion is desired. Those factors include carbon dioxide, octenol, lactic acid, acetone), and heat, to name a few. Respiratory or digestive by-products are believed to cause the mosquitoes and biting flies that have been attracted by the heartbeat sound to go into a feeding or biting mode. Whereas the suitable heartbeat sound will attract insects from a distance to the proximity of the insect control unit, a by product of respiration or digestion causes certain targeted insects to land directly on the insect control unit where they are captured or eradicated.
In a preferred embodiment, a single insect control station can be used to attract insects by the system and method described. Through the continued use of the inventive system, an insect population in the vicinity of the control station can drop to a level below which the insect no longer functions as a disease vector. Research has shown that all or at least a part of the low frequency heartbeat sound can sensitize biting insects to feeding stimulants. For example, whereas other insect control devices may typically use 200 to 500 milliliters or more of carbon dioxide per minute to cause mosquitoes to exhibit a heightened feeding behavior, our insect control unit needs only about 25 mililiters to about 125 milliliters of carbon dioxide per minute to cause a similar feeding behavior. This results in a significant cost savings, and because of the smaller carbon dioxide requirements, makes possible the construction of easily portable units for field studies and weekend use. In addition to sensitizing insects to feeding stimulants, the low frequency sound also desensitizes biting insects to the presence of their normal prey. Whereas other insect control devices can increase bite counts in areas of use, the control unit of the present invention can significantly decrease the number of bite counts in areas of use. Indeed during several field studies where literately hundreds of mosquitoes or biting flies were flying around and landing on the insect control surfaces of the unit, nearby human observers were not bitten.
In one particular aspect, the invention provides a method for attracting insects to at least one control station that is remotely positioned relative to a central node in a system of control stations. The method according to this first aspect of the invention includes the steps of generating at the central node an acoustic wave, propagating the acoustic wave through the hollow tubing, and emitting the acoustic wave at the control station to attract insects into an attractant zone proximate to the control station.
In another particular aspect, the invention provides a method for establishing a barrier to blood-sucking insects. The method according to this aspect of the invention defines a barrier by arranging plural control stations relative to a central distribution point. According to this method, a central distribution point is provided with a sound source that generates a sound wave suitable for attracting or repelling blood-sucking insects. A branching network of hollow tubing is established in which the hollow tubing is communicatively connected to the central distribution point for receiving the generated sound wave. A plurality of control stations is connected to the branching network of hollow tubing so that there is no more than a prescribed spacing between adjacent ones of the plural control stations. At least the sound wave is conveyed from the central distribution point to the plural control stations for emanation thereat to define the barrier.
In a further aspect, the invention provides a method for establishing a barrier to animal pests such as deer and rabbits, to name a few. This method is similar to the method described above, however, the sound source in this method generates a sound wave that is simulative of at least a portion of a heartbeat suitable for repelling animal pests. Otherwise, the method steps are as described above and result in sound waves emanating at the control stations to define a barrier to repel animal pests and undesired creatures.
In a preferred embodiment, a self-contained insect control station is used either alone or in coordination with other self-contained insect control stations. Each insect control station has a sound source that generates a sound wave that is simulative of a least a portion of a heartbeat. In the attraction mode, each insect control station emanates a byproduct of respiration or digestion to induce landing of the insect on the insect control station.
Methods in accordance with the foregoing aspects of the invention can include one or more of the additional steps indicated below:
a. drawing insects into the hollow tubing once attracted into the attractant zone through the use of a source of negative pressure;
b. constructing the acoustic wave so that it is simulative of at least a portion of a heartbeat;
c. releasing one or more of the byproducts of respiration or a volatile chemical from digestion (octenal) in the support tube or proximate to the control station;
d. releasing an insect pesticide proximate to the control station; and providing a pathogen to biting arthropods or other insects proximate to or upon the control station.
e. Providing a glue surface specifically designed for a high capture rate of mosquitoes and biting flies proximate to or upon the control station.
The method also can include steps and features described below in connection with the Drawing Figures and the Detailed Description of Certain Preferred Embodiments.
The significant advantage of the present invention is that a highly cost-effective and environmentally safe technique is provided to control the insect population, and particularly the population of mosquitoes and biting flies. The technique of the present invention can be employed on a large scale by municipalities to control mosquitoes and biting flies throughout large public areas, or can be employed by an individual to control the mosquito and biting fly population in a backyard or in the home. The device of the present invention can kill attracted mosquito or flies by various techniques and equipment.
In accordance with yet a further aspect of the invention, an insect control station includes a means for generating a prescribed analog signal, a speaker connected to receive the prescribed analog signal and to deliver acoustic energy to a resonator positioned in the path of the delivered acoustic energy. The control station can be implemented within a single housing or with some of its components housed separately from other components.
In one particular arrangement, the analog signal is generated using a memory and a digital to analog converter. The memory stores a digitized audio sample and delivers the digitized audio sample in response to a strobe signal. The digital to analog converter (DAC) has an input communicatively coupled to the memory and an output that outputs analog signals. The speaker receives these analog signals from the DAC and delivers the acoustic energy to the resonator.
In another particular arrangement, the analog signal is generated using a digital signal processor. The digital signal processor (DSP) is programmed with an algorithm that generates one or more prescribed analog signals that are provided to the speaker and the resonator.
In yet another particular arrangement, the analog signal is generated by mechanical elements and then provided to the speaker and the resonator.
Preferably, the acoustic energy emitted from the control stations of any of these arrangements is simulative of at least a portion of a heartbeat.
The control station of any of these arrangements can include tubing between the speaker and the resonator, with the tubing defining a path for the delivery of acoustic energy to the surrounding area. Alternatively, and in accordance with a preferred arrangement for a stand-alone control station, a resonator is spaced above the ground or other supporting surface by tubing, with a speaker positioned proximate a resonator and the resonator coupled about the speaker for delivery of the acoustic energy to the surrounding area. The tubing has an exterior surface that can be provided with a striped pattern to visually attract certain insects to the control station.
In a further, optional, arrangement, the control station can include a source of negative pressure and an inlet proximate the resonator that is sized to receive insects that are drawn through the inlet in response to negative pressure.
In yet another, optional, arrangement, a pesticide or a gluey substance is affixed to the control station, for example, on or proximate to the resonator.
In still a further, optional, arrangement, the control station includes a mechanism for delivering one or more feeding stimulants from within the support tube or proximate to the resonator. The feeding stimulants can include: carbon dioxide, heat, acetone, lactic acid, octenol, or other byproducts of respiration or digestion.
A preferred embodiment of an insect control station which can be constructed according to the invention comprises a memory which stores a digitized audio sample and delivers the digitized audio sample in response to a strobe signal, a digital to analog converter (DAC) having an input communicatively coupled to the memory and an output that outputs analog signals, a circuit which repeatedly delivers the strobe signal, an amplifier connected to the output of the DAC, a speaker connected to receive the analog signals from the amplifier and to deliver acoustic energy that is simulative of at least a portion of a heartbeat, tubing positioned below the speaker for spacing the speaker from ground (or some other support surface) and for delivering heat or other feeding stimulants and a resonator positioned in the path of the delivered acoustic energy, the resonator presenting a surface that vibrates in response to the acoustic energy and which can support a pesticide or gluey substance for controlling a local insect population.
These further objects, features, and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings.